Hydraulic reservoir breather caps are commonly employed to receive high-velocity air impregnated with suspended oil droplets from machinery. Such breather caps filter the air that is thus being expelled into the atmosphere.
A common problem in the current design of a hydraulic reservoir breather cap is its inability to adequately filter or separate the oil droplets suspended in the rapidly expelled air. Presently, oil droplets that are filtered from vented air tend to pool and drip from the undersides of the cap onto surrounding surfaces. Also, not all of the suspended, air-laden oil is separated from the air as it exits the cap. Such vented air is, therefore, a pollutant.
The present invention seeks to more adequately separate the suspended, airborne oil from the air exiting the hydraulic reservoir breather cap. The breather cap designs of the present invention slow the high-speed air within an internal chamber, causing the heavier oil droplets to impinge upon a deflector plate or a deflecting chamber surface. The deflector plate or deflecting surface prevents the high-speed air from directly venting to the atmosphere. The suspended oil impinging upon the plate or deflecting surface is then released from the slowed air, which is then allowed to vent from the breather cap. The separated oil droplets pool upon the deflector plate or deflecting surface and drop to the bottom of the breather cap chamber. From there, the oil drops back into the oil reservoir. Being substantially free of oil, the vented air is now lighter and rises above the deflector plate, where it exits the cap. Thus, this air is no longer considered a pollution problem.